Blacking or dressing for metal surfaces.



the ingredients shall be of a nature to ti ailv t t' l lilil lll STATESPATENT OFFICE.

DUNCAN R. FRANKLIN, OF NEW YORK, N. Y., ASSIGNOR TO S. M. IlllXjBY &;COMPANY, OF NEW YORK, N. Y., A CORPORATION 01? NEW YORK.

BLACKING 0R DRESSING FOR METAL SURTJACES.

Specification of Letters Patent.

Application filed September 10, 1909.

No Drawing.

Patented Aug. 22, 1911.

Serial No. 517,050.

To all whom it may concern:

Ile it known that I, DUNCAN R. FRANK- m.\'. a citizen of the UnitedStates and a resident ot- New York, county of New York, and State of NewYork, have invented certain new and useful inprovemc'uts in lilackinesor Dressings tor Metal Surfaces, of which the following is aspecification.

My invention relates to blackings or dressings for metal surfaces andmore especially to that class which are used for polishing stoves andothe' articles which are inlcmhul to be heated.

in certain prior compositions for stove blaekings or polishes itv hasbeen customary to use graphite or other carbonaceous material and insome instances to combine with this a tiller.Insuchcompositions,however, the tiller has been of a character. whichwhen subjected to heat decomposes, such that it is not united in any wayto the iron or metallic surl'aco and r ulily becomes loosened so thatthe whole coating or polish soon wears away utter a short usage.

it is one object ol' my inycntion to pro vide a composition in which atleast one of adhere to the surl'ace of the metallic iron or othermetallic surface. and, especially when heat is applied thereto; whichwill more intimately unite with the metallic Surtace in such a way thata coating is secured which will be very permanently tixcd by the heatingand wears almost indciinitely'as coin; )u1'tul with prior polishes. Inorder to bring about this result I provide a dressing containing a metalin a form which under the action of heat turns into a black compoumlwhich readily and firmly unites with the iron.

Preferably the metal is applied in the form of an emulsion of a compoundof the metal so that when heat is applied the com pound breaks up.'l'orming a. black oxid of the metal which is very stable and stronglyadheres to the metallic surface. In many instances I also find itadvantageous to use a black tiller ot carlmnaceous material.

The pret'erred form of composition which l use consists of a wateremulsion or solution oti cobalt hydrate and a tiller of graphite orcarbon black. The use of the hydrate or l'lydroxicl of cobalt ispreferable and advantageous since it dmrmnposes at comparatively lowtemperatures, v. a. about 3:25" l'b, that is, temperatures tound in theordimiry stove while baking paalry, etc.

When this composition is applied to a stove r other iron surl'ace whichis attcr ward heated, the heat canFcs a decomposition of the hydrate andthe l'ormatirm ol. :1 black oxid of cobalt. This; black oxid may be acomposition of several ol the cobalto-eobaltic oxide. The oxid thustor-med while in contact with the iron which is in a heated condition isfirmly united with the iron and can only be removed by slow do grees inthe ordinary use ol the stove. .\n;\' further heating of the surface hasno ell'ect on the composition except to more tirmly fix it in position.l urthermore when ap plied to stoves or other iron snrtaccsthe. metallicoxid permita the surface turn ng red which is a common .()t('ltl'It-|lt't doc o the formation of red oxid ol' iron.

Although prefer to use cobalt lnxdralc. nevertheless other cobalt.compounds only be used. such as the salts thcreol and cVcn the oxidsthemselves although it is impon taut; that they decompose or linally rcailt in a black compound or compoumla with the ordinary heat of stoves:or oclow no i". lompounds which do not re ult in the lack compound orcon'lpounds at the ordi :ary heat of stoves are obviously conniwrciaitvunfit for a stove blacking'. l urtherniorc although I consider thecobalt compoun-ls to have many advantages over any othcrs, neverthelessfor some I)lll'])ll t)H certain compounds of other metals and even themetals themselves may be u ed with mlvantageous results. in order to getgood results, how-- ever, I prefer the use of some metal or metalliccompound which under lhc action ot' heat decomposes at a snllicientlylow temperature into a black oxid or oxids which lirmly adhere to theiron, possiblydonning a chemical combination therewith. For this.purpose would select metals ot the iron groupt .ier than iron as beingbest suited, sinc under some conditions nickel compounds term a veryellicicnt. blackingzj.

I am aware that certain copper compounds and especially copper saltsliu\'c been suggested under certain conditions. in this case thecompound breaks up and the black oxid of copper is 't'ornn-d. l tlnd.however, that copper compounds do not.

give as good results as the cobalt compounds since the copper compoundsare very liable to decompose into oxids other than the black oxide, andthe cobalt dressing'has *many advantages over the copper dressing.

held therein in suspension, or in solution, or'

bath. In any of these forms, however, the dressing is easily applied tothe metallic surfacein such a manner that it is evenly distributedthereover and brought into intimate contact with the surface.

Although I have described my improvements in great detail, neverthelessI do not desire to be limited -to the specific compounds mentioned,except as specified hereafter in the claims, 'since many modifica-"tions within the spirit and. scope of my in- .ventmn will occur to theskilled chemist.

Having fully and clearly described my invention, what I desire to secureby Letters Patent is 1-. A blacking or dressing for iron sur facesincluding an emulsion of cobalt hydrate; capable of being decomposedunder the action of heat to cobalt;

2. A blackln'g or dressing for iron surproduce black oxid of I facesincluding a black filler of graphite and a 'Water eniuision of cobalthydrate capable of being decomposed under the action of heat to produceblack oxid of cobalt.

3. A blacking or dressing for iron surfaces including an emulsion of acobalt eon pound capable of being decomposed by 4. A'blacking ordressing for metal sur- '1. faces including cobalt in a form capable 0tbeing changed by heat to produce an oxid of cobalt at a temperaturebelow 400 F.

5. A blacking or dressing for metal sur.

faces including cobalt in a form capable of being changed by heat at atemperature be low 400 F. to produce an oxid of cobalt and a blackfiller. v

6. A blacking or dressing for inetalsun faces including acompound of ametal of the iron group capable of and in a form de signed to be changedinto an oxid under the action of heat at a temperature below 400 F.

7. A blacking or dressing for metal surfaces including a metal of theiron group capable "of, and in a form designed to be changed into ablack compound under the action of heat at a temperature below 400 F.

8. A ,blacking or dressing for metal surfaces including a metal of theiron group capable of and in a form designed to be changed into ablackcompound under the action of heat at about 325 F. and a blackfiller.

9. A blacking or dressing for metal surfaces including a liquidcontaining a cobalt compound designed to be decomposed by heat below 400F. to produce a black. oxid of cobalt, and a carbonaceous filler. I

In testimony whereof, I have signed my name to this specification, inthe presence of two subscribing witnesses. v

DUNGAN R. FRANKLIIL Witnessesz' GORHAM ()noser, EDWIN Sir-ens.

